Key to the Brochure

Time frame:

Time frames will naturally vary based on numerous factors (agency
procedures, number of stakeholders, need for additional right-ofway).
The scale is meant as a general guide. One circle indicates
a short time frame for implementation perhaps in as little as a few
months or up to 1 year. Example short term strategies include
signage improvements, signal timing changes, and sight distance
improvements. Two circles indicates a medium time frame of 1-2
years. Example medium term strategies include channelization
improvements, system-wide signal improvements, and minor
geometric improvements. Three circles indicates a longer time
frame of over 2 years. These strategies will typically require major
construction or right-of-way acquisition.

Costs:

Costs will also vary considerably and are affected by local
conditions. Costs are ranked as: low, moderate, moderate to high,
and high. The scale is meant to reflect costs relative to the other
strategies described in the category (signalized or unsignalized).

Effectiveness:

This section will discuss any research or evaluations that have
been done to ascertain the effectiveness of the particular strategy.
Three descriptors are used to identify to what degree the strategy
has been evaluated:

Proven: Those strategies that have been used in one or more
locations and for which properly designed evaluations have been
conducted that show it to be effective. These strategies may
be employed with a good degree of confidence, but with the
understanding that any application can lead to results that vary
significantly from those found in previous evaluations. Crash
reduction factors reported are typically based on valid research
methods.

Tried: Those strategies that have been implemented in a
number of locations and may even be accepted as standards or
standard approaches, but for which there have not been found
valid evaluations. These strategies, while frequently or even
generally used, should be applied with caution; users should
carefully consider the attributes cited in the guide and relate them
to the specific conditions for which they are being considered.
There can be some degree of assurance that implementation will
not likely have a negative impact on safety and will very likely
have a positive one. Crash reduction factors reported are not
necessarily based on valid research methods and should be used
with caution.

Experimental: Those strategies that have been suggested and
that at least one agency has considered sufficiently promising to
try on a small scale in at least one location. These strategies should
be considered only after the others have been determined to be
inappropriate or unfeasible. Even where they are considered, their
implementation should initially occur using a very controlled and
limited pilot study that includes a properly designed evaluation
component.

This brochure is a quick reference to the countermeasures
described in the NCHRP Report 500 volumes on reducing
crashes at unsignalized (Volume 5) and signalized (Volume
12) intersections and is a supplement to individual
guide sheets for each of the 77 countermeasures. These
documents describe and illustrate the countermeasures
in greater detail.

Unsignalized Intersection Safety Strategies

COST

Safety Concern: High frequency of right-angle
crashes attributed to:

Low

Moderate

Moderate-High

High

nearby driveways

A2, B12, C1, C2, C4

A1

B8

traffic from minor street

B12, C1, C2, C4, D2

D1

B8

B13, F3

skewed intersection

B16, C3, F3

poor sight distance

C1, C2, C4, H3

D1

C3, F3

drivers misjudging gaps

D2, H3

D1

F3

not enough gaps for drivers

D3

B14, F3

driver unaware of intersection

E1, 5-E9, E10, E11

E3

nighttime conditions

E10

E2

failure to yield at stop or yield sign

E1, E4-E9, E11

G1

F3

possible signal location

F1, F3

heavy but balanced traffic flow

F2

F3

speed differentials of vehicles

H3

H1, H2

F3

Safety Concern: High frequency of rear-end crashes attributed
to:

left turning vehicles hit from behind

B4

B1, B2

F3

left opposing vehicles hit from behind

B3

F3

trucks and RVs entering divided highway

B5

speed differential of entering vehicles

B6, B9

F3

right turning vehicles hit from behind

B6, B7

B16, F3

appoaching vehicles hit from behind

B10

no left turn lane and high opposing traffic

B11, B12

B13

driver unaware of intersection

E1, E5-E9, E10, E11

E3

nighttime conditions

E8, E10

E2

speed differentials of vehicles

H3

H1, H2

F3

Safety Concern: High frequency of left-turn crashes attributed
to:

left turn vehicles hit by opposing traffic

C2

B1, B17

B3

B15, F3

trucks and/or RVs entering divided highway

B5

no left turn lane and high opposing traffic

B11, B12

B17

B13

nighttime conditions

E10

E2

heavy but balanced traffic flow

F2

F3

Poor sight distance

C2, B11, B12

B17

B13

Safety Concern: High frequency of sideswipe crashes attributed
to:

speed differential of entering vehicles

B9

F3

vehicles within intersection

I1, I2

vehicles approaching intersection

I3

Safety Concern: High frequency of run off road crashes:

approaching intersection

B10

Safety Concern: High frequency of pedestrian/bicycle crashes:

at the intersection

B18, H2

Safety Concern: Address overall safety issues:

violation of traffic laws

G2

Note: Counter measures indicated on the table
are possible treatments for individual crash problems. Implementation should
be based on individual circumstances and studies.

CATEGORY A: IMPROVE MANAGEMENT OF ACCESS

A1 – Implement driveway closures/relocations (HTML | PDF). WHERE TO USE – Unsignalized intersections with high crash frequencies related to driveways adjacent to the intersection. Generally, driveways within 250 feet of the intersection are the greatest concern. Time: Short. Effectiveness: Tried

A2 – Implement driveway turn restrictions (HTML | PDF). WHERE TO USE – Driveways located near unsignalized intersections that experience high crash frequencies but that cannot practically be closed or relocated. Time: Short. Effectiveness: Tried.

CATEGORY B: REDUCE CONFLICTS THROUGH GEOMETRIC DESIGN IMPROVEMENTS

B1 – Provide left-turn lanes at intersections (HTML | PDF). WHERE TO USE – Unsignalized intersections with a high frequency of crashes resulting from the conflict between (1)
vehicles turning left and following vehicles and (2) vehicles turning left and opposing through vehicles. Time: Medium. Effectiveness: Proven.

B2 – Provide longer left-turn lanes at intersections (HTML | PDF).WHERE TO USE – Unsignalized intersections with existing leftturn lanes that are not long enough to store all left-turning vehicles and have a high frequency of rear-end crashes resulting from the conflict between vehicles waiting to turn left and following vehicles. Time: Medium. Effectiveness: Tried.

B3 – Provide offset left-turn lanes at intersections (HTML | PDF).
WHERE TO USE – Unsignalized intersections with a high frequency of crashes between vehicles turning left and opposing through vehicles, as well as rear-end crashes between through vehicles on the opposing approach. Also at intersections on divided highways with medians wide enough to provide the appropriate offset but can be implemented on approaches without medians if sufficient width exists. Time: Medium. Effectiveness: Tried.

B4 – Provide bypass lanes on shoulders at
T-intersections
(HTML | PDF).
WHERE TO USE – At three-legged unsignalized intersections on two-lane highways with moderate through and turning volumes, especially intersections that have a pattern of rearend collisions involving vehicles waiting to turn left from the highway. Time: Short. Effectiveness: Tried.

B5 – Provide left-turn acceleration lanes at divided highway intersections (HTML | PDF).
WHERE TO USE – Unsignalized intersections on divided highways that experience a high proportion of rear-end crashes related to the speed differential caused by vehicles turning left onto the highway. Also where intersection sight distance is inadequate or where there are high volumes of trucks or recreational vehicles entering the divided highway. Time: Medium. Effectiveness: Tried.

B6 – Provide right-turn lanes at intersections
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with a high frequency of rear-end crashes resulting from conflicts between (1) vehicles turning right and following vehicles and (2) vehicles turning right and through vehicles coming from the left on the cross street. Time: Medium. Effectiveness: Proven.

B7 – Provide longer right-turn lanes at intersections
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with an existing right-turn lane that is not long enough to store all right-turning vehicles and that are experiencing a high frequency of rear-end crashes resulting from the conflict between vehicles waiting to turn right and following vehicles. Time: Medium. Effectiveness: Tried.

B8 – Provide offset right-turn lanes at intersections
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with a high frequency of crashes between vehicles on the minor road that are turning left, turning right, or proceeding straight through, and vehicles on the major road. Time: Medium. Effectiveness: Tried.

B9 – Provide right-turn acceleration lanes at
intersections
(HTML | PDF).
WHERE TO USE – Unsignalized intersections that experience a high proportion of rear-end and/or sideswipe crashes related to the speed differential caused by vehicles making a rightturn maneuver onto the highway.
Time: Medium. Effectiveness: Tried.

B10 – Provide full-width paved shoulders in intersection areas
(HTML | PDF).
WHERE TO USE – Unsignalized intersections on divided highways with no shoulder or shoulder widths less than 8 feet that experience a high proportion of run-off-road crashes as a result of avoidance maneuvers or a high proportion of rearend crashes that could have been avoided had a full-width paved shoulder been provided. Time: Medium. Effectiveness: Tried.

B11 – Restrict or eliminate turning maneuvers by signing
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with patterns of
crashes related to particular turning maneuvers where it is
impractical to reduce that pattern of crashes by improving sight
distance or providing a left-turn or shoulder bypass lane.
Time: Short. Effectiveness: Tried.

B12 – Restrict or eliminate turning maneuvers by providing channelization or closing median openings
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with patterns of
crashes related to particular turning maneuvers where it is
impractical to reduce that pattern of crashes by improving
sight distance or providing a left-turn or shoulder bypass lane.
Also, at locations where it is possible to restrict or eliminate
turning maneuvers by providing channelization or by closing
the median opening.
Time: Short. Effectiveness: Tried.

B13 – Close or relocate "high-risk" intersections
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with high levels
of intersection-related crashes that other strategies have not
been successful in reducing or for which other strategies
are not considered appropriate. Also at locations where a
particular strategy such as installing a turn lane or increasing
sight distance is impractical at the current location, but could
be applied if the intersection were moved.
Time: Long. Effectiveness: Tried.

B14 – Convert four-legged intersections to two T-intersections
(HTML | PDF).
WHERE TO USE – Unsignalized four-legged intersections with
very low through volumes on the cross street.
Time: Medium. Effectiveness: Tried.

B15 – Convert offset T-intersections to four-legged
intersections
(HTML | PDF).
WHERE TO USE – Unsignalized offset T-intersections where
through volumes on the cross street are very high.
Time: Medium. Effectiveness: Tried.

B17 – Use indirect left-turn treatments to minimize conflicts at divided highway intersections
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with operational
and safety problems that can be traced to difficulties of
accommodating left-turn demand.
Time: Medium. Effectiveness: Tried.

B18 – Improve pedestrian and bicycle facilities to reduce conflicts between motorists and nonmotorists
(HTML | PDF).
WHERE TO USE – Unsignalized intersections that experience
crashes involving pedestrians and/or bicyclists with motor
vehicles or that have the potential for such crashes.
Time: Medium. Effectiveness: Tried/Proven.

CATEGORY C: IMPROVE SIGHT DISTANCE

C1 – Clear sight triangles on stop- or yield-controlled
approaches to intersections
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with restricted
sight distance and patterns of crashes related to lack of sight
distance, where sight distance can be improved by clearing
roadside obstructions without major construction.
Time: Short. Effectiveness: Tried.

C2 – Clear sight triangles in the medians of divided highways near intersections
(HTML | PDF).
WHERE TO USE – Unsignalized intersections on divided
highways with (a) fixed sight obstructions in the median near
the intersection and (b) patterns of crashes related to the lack
of sight distance.
Time: Short. Effectiveness: Tried.

C3 – Change horizontal and/or vertical alignment of
approaches to provide more sight distance
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with restricted sight
distance due to horizontal and/or vertical geometry and with
patterns of crashes related to that lack of sight distance that
cannot be ameliorated by less expensive methods.
Time: Long. Effectiveness: Tried.

D1 – Provide an automated real-time system to
inform drivers of the suitability of available gaps for
making turning and crossing maneuvers
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with a high frequency of right-angle collisions due to restricted sight distance.
Time: Medium. Effectiveness: Experimental.

D2 – Provide innovative signs and markings to assist drivers in judging the suitability of available gaps for making turning and crossing maneuvers
(HTML | PDF).
WHERE TO USE – Unsignalized intersections where crash data
shows a high occurrence of crashes where vehicles on
secondary roadways intersecting at grade misjudge the gap
between approaching vehicles.
Time: Medium. Effectiveness: Experimental.

D3 – Retime adjacent signals to create gaps at stopcontrolled intersections
(HTML | PDF).
WHERE TO USE – Unsignalized intersections (between signalized intersections) with a high frequency of right-angle or turningrelated
crashes due to a lack of sufficient gaps in through traffic on the major road.
Time: Short. Effectiveness: Tried.

CATEGORY E: IMPROVE DRIVER AWARENESS

E1 – Improve visibility of intersections by providing
enhanced signing and delineation
(HTML | PDF).
WHERE TO USE – Unsignalized intersections that are not clearly
visible to approaching motorists, particularly approaching
motorists on the major road. The strategy is particularly
appropriate for intersections with patterns of rear-end, rightangle,
or turning crashes related to lack of driver awareness of
the presence of the intersection.
Time: Short. Effectiveness: Tried.

E2 – Improve visibility of the intersection by
providing lighting
(HTML | PDF).
WHERE TO USE – Unsignalized, unlit intersections with substantial
patterns of nighttime crashes. In particular, patterns of rear-end,
right-angle, or turning crashes on the major-road approaches
to an unsignalized intersection may indicate that approaching
drivers are unaware of the presence of the intersection.
Time: Medium. Effectiveness: Proven.

E3 – Install splitter islands on the minor-road
approach to an intersection
(HTML | PDF).
WHERE TO USE – Minor road approaches to unsignalized
intersections where the presence of the intersection or the
stop sign is not readily visible to approaching motorists. The
strategy is particularly appropriate for intersections where the
speeds on the minor road are high.
Time: Medium. Effectiveness: Tried.

E4 – Provide a stop bar (or provide a wider stop bar)
on minor-road approaches
(HTML | PDF).
WHERE TO USE – Approaches to unsignalized intersections
having traffic control devices that are not currently being
recognized by some approaching motorists. Locations should
be identified by patterns of crashes related to lack of driver
recognition of the traffic control device (e.g., right-angle
crashes related to stop sign violations).
Time: Short. Effectiveness: Tried.

E5 – Install larger regulatory and warning signs at
intersections
(HTML | PDF).
WHERE TO USE – Approaches to unsignalized intersections with
patterns of rear-end, right-angle, or turning collisions related
to lack of driver awareness of the presence of the intersection.
Time: Short. Effectiveness: Tried.

E6 – Call attention to the intersection by installing rumble
strips on intersection approaches
(HTML | PDF).
WHERE TO USE – Approaches to unsignalized intersections with
traffic control devices that are not currently being recognized
by some approaching motorists. Locations should be identified
by patterns of crashes related to lack of driver recognition of
the traffic control device (e.g., right-angle crashes related to
stop sign violations). Rumble strips should be considered only
after an adequate trial of less intrusive treatments.
Time: Short. Effectiveness: Tried.

E7 – Provide dashed markings (extended left
edgelines) for major-road continuity across the
median opening at divided highway intersections
(HTML | PDF).
WHERE TO USE – Unsignalized intersections on divided
highways. The strategy is particularly appropriate for
intersections with patterns of rear-end, right-angle, or
turning crashes related to lack of awareness by the driver
on the minor road to the presence of the intersection.
Time: Short. Effectiveness: Tried.

E8 – Provide supplementary stop signs mounted
over the roadway
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with patterns
of right-angle crashes related to lack of driver awareness
of the presence of the intersection. In particular, it might be
appropriate to use this strategy at the first stop-controlled
approach (possibly of a series) located on a long stretch of
highway without any required stops, or at an intersection
located after a sharp horizontal curve.
Time: Short. Effectiveness: Tried.

E9 – Provide pavement markings with
supplementary messages, such as STOP AHEAD
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with patterns of
rear-end, right-angle, or turning crashes related to lack of
driver awareness of the presence of the intersection.
Time: Short. Effectiveness: Tried.

E11 – Install flashing beacons at stop-controlled intersections
(HTML | PDF).
WHERE TO USE – Unsignalized intersections with patterns of
right-angle crashes related to lack of driver awareness of the
intersection on an uncontrolled approach and lack of driver
awareness of the stop sign on a stop-controlled approach.
Time: Short. Effectiveness: Tried.

CATEGORY F: CHOOSE APPROPRIATE INTERSECTION TRAFFIC CONTROL

F1 – Avoid signalizing through roads
(HTML | PDF).
WHERE TO USE – Medium- to high-volume unsignalized
intersections where installation of signals is being considered.
Before a decision to install a signal is made, adequate
consideration should be given to less restrictive forms of
traffic control.
Time: Long. Effectiveness: Tried.

F3 – Provide roundabouts at appropriate locations
(HTML | PDF).
WHERE TO USE – Unsignalized intersections that are
experiencing right-angle, rear-end, and turning crashes.
Roundabouts are appropriate at most intersections, and
at intersections with large traffic delays roundabouts
are oftentimes a superior alternative to signalization.
Roundabouts can also be very effective at intersections with
complex geometry (e.g., more than four approach roads)
and intersections with frequent left-turn movements.
Time: Long. Effectiveness: Proven.

G2 – Provide targeted public information and
education on safety problems at specific
intersections
(HTML | PDF).
WHERE TO USE – Jurisdictions that have experienced a large
number of safety problems at unsignalized intersections.
Time: Short. Effectiveness: Tried.

I2 – Provide a double yellow centerline on the median opening of a divided highway at intersections
(HTML | PDF).
WHERE TO USE – Unsignalized intersections on divided highways
that are experiencing a high degree of crashes caused by sideby-
side queuing and angle stopping within the median area.
Time: Short. Effectiveness: Tried.

Note: Counter measures indicated on the table
are possible treatments for individual crash problems. Implementation
should be based on individual circumstances and studies.

CATEGORY A: REDUCE FREQUENCY AND SEVERITY OF INTERSECTION CONFLICTS THROUGH TRAFFIC CONTROL AND OPERATIONAL IMPROVEMENTS

A1 – Employ Multiphase Signal Operation
(HTML | PDF).
WHERE TO USE – Signalized intersections with a high frequency
of angle crashes involving left turning and opposing through
vehicles. A properly timed protected left-turn phase can also
help reduce rear-end and sideswipe crashes between leftturning
vehicles and the through vehicles behind them.
Time: Short. Effectiveness: Tried/Proven.

A2 – Optimize Change Intervals
(HTML | PDF).
WHERE TO USE – Signalized intersections with a high frequency
of crashes related to change interval lengths that are possibly
too short. These crashes include angle crashes between
vehicles continuing through the intersection after one phase
has ended and the vehicles entering the intersection on the
following phase. Rear-end crashes may also be a symptom of
short change intervals.Time: Short. Effectiveness: Proven.

A3 – Restrict or eliminate turning maneuvers (including right turns
on red) (HTML
| PDF).
WHERE TO USE – Signalized intersections with a high frequency of crashes related
to turning maneuvers. For right turn on red (RTOR), the target of this strategy
is right-turning vehicles that are involved in rear-end or angle crashes with
cross-street vehicles approaching from the left or vehicles turning left from
the opposing approach, and crashes involving pedestrians. Time:
Short. Effectiveness: Tried.

A4 – Employ signal coordination
(HTML | PDF).
WHERE TO USE – Signalized intersections with a high frequency
of crashes related to turning maneuvers. For right turn on red
(RTOR), the target of this strategy is right-turning vehicles that
are involved in rear-end or angle crashes with cross-street
vehicles approaching from the left or vehicles turning left from
the opposing approach, and crashes involving pedestrians.
Time: Medium. Effectiveness: Proven.

A6 – Improve operation of pedestrian and bicycle
facilities at signalized intersections
(HTML | PDF).
WHERE TO USE – Signalized intersections with high
frequencies of pedestrian and/or bicycle crashes. Also on
routes serving schools or other generators of pedestrian
and bicycle traffic.
Time: Short. Effectiveness: Tried/Proven.

A7 – Remove unwarranted signal
(HTML | PDF).
WHERE TO USE – Signalized intersections where the traffic
volumes and safety record do not warrant a traffic signal.
Time: Short. Effectiveness: Proven.

B2 – Provide/improve right-turn channelization
(HTML | PDF).
WHERE TO USE – Signalized intersections with a high frequency
of rear-end collisions resulting from conflicts between: (1)
vehicles turning right and following vehicles; and (2) vehicles
turning right and through vehicles coming from the left on the
cross street.
Time: Medium. Effectiveness: Proven.

B3 – Improve geometry of pedestrian and bicycle
facilities
(HTML | PDF).
WHERE TO USE – Signalized intersections with high
frequencies of pedestrian and/or bicycle crashes and on
routes serving schools or other generators of pedestrian
and bicycle traffic.
Time: Short. Effectiveness: Tried/Proven.

B4 – Revise geometry of complex intersections
(HTML | PDF).
WHERE TO USE – Signalized intersections with high levels of
crashes on a leg where other low-cost strategies have not been
successful or are not considered appropriate.
Time: Long. Effectiveness: Tried/Proven.

B5 – Construct special solutions
(HTML | PDF).
WHERE TO USE – Signalized intersections with high
frequencies of crashes that are not reduced through other
lower-cost solutions.
Time: Long. Effectiveness: Tried.

CATEGORY C: IMPROVE SIGHT DISTANCE AT SIGNALIZED INTERSECTIONS

C1 – Clear sight triangles
(HTML | PDF).
WHERE TO USE – Signalized intersections where there is a high
frequency of crashes between vehicles turning right on red
from one street and through vehicles on the other street
or crashes involving left turning traffic where landscaped
medians are present.
Time: Short. Effectiveness: Tried.

CATEGORY D: IMPROVE DRIVER AWARENESS OF INTERSECTIONS AND SIGNAL CONTROL

D1 – Improve visibility of intersections on approach(es)
(HTML | PDF).
WHERE TO USE – Signalized intersections with a high frequency of crashes attributed to drivers being unaware of the presence
of the intersection.
Time: Short. Effectiveness: Tried.

D2 – Improve visibility of signals and signs at
intersections
(HTML | PDF).
WHERE TO USE – Signalized intersections with a high frequency
of right-angle and rear-end crashes occurring because drivers
are unable to see traffic signals and signs sufficiently in advance
to safely negotiate the intersection being approached.
Time: Short. Effectiveness: Tried.

CATEGORY E: IMPROVE DRIVER COMPLIANCE WITH TRAFFIC CONTROL DEVICES

E1 – Provide public information and education
(HTML | PDF).
WHERE TO USE – Signalized intersections with a high frequency
of crashes related to drivers either being unaware of (or
refusing to obey) traffic laws and regulations that impact traffic
safety (especially red-light running, speeding, and not yielding
to pedestrians).
Time: Short. Effectiveness: Tried.

E2 – Provide targeted conventional enforcement of traffic laws
(HTML | PDF).
WHERE TO USE – Signalized intersections with a high frequency
of crashes related to drivers either being unaware of (or
refusing to obey) traffic laws and regulations that impact
traffic safety.
Time: Short. Effectiveness: Tried.

E5 – Control speed on approaches
(HTML | PDF).
WHERE TO USE – Signalized intersections with a high frequency
of crashes attributed to drivers who intentionally disobey
posted approach speed limits.
Time: Medium. Effectiveness: Experimental.

CATEGORY F: IMPROVE ACCESS MANAGEMENT NEAR SIGNALIZED INTERSECTIONS

F1 – Restrict access to properties using driveway
closures or turn restrictions
(HTML | PDF).
WHERE TO USE – Signalized intersections with high crash
frequencies related to driveways adjacent to the intersection.
Generally, driveways within 250 feet of the intersection are
the greatest concern.
Time: Short. Effectiveness: Tried.

F2 – Restrict cross-median access near intersections
(HTML | PDF).
WHERE TO USE – Approaches to signalized intersections with
a high frequency of crashes involving drivers making turns
across medians.
Time: Short. Effectiveness: Tried.

CATEGORY G: IMPROVE SAFETY THROUGH OTHER INFRASTRUCTURE TREATMENTS

G1 – Improve drainage in intersection and on approaches (HTML
| PDF).
WHERE TO USE – Signalized intersections with a high frequency of crashes that
are related to poor drainage. Such crashes involve vehicles that hydroplane
and, hence, are not able to stop when required. Time: Medium.
Effectiveness: Tried.

G2 – Provide skid resistance in intersection and on approaches
(HTML | PDF).
WHERE TO USE – Signalized intersection approaches where
skidding is determined to be a problem, especially in wet
conditions.
Time: Medium. Effectiveness: Tried.

G3 – Coordinate closely spaced signals near at-grade railroad crossings
(HTML | PDF).
WHERE TO USE – Signalized intersections in close proximity to
at-grade railroad crossings with a high frequency of crashes.
This situation presents a significant potential for vehicletrain
crashes, but vehicle-vehicle crashes could also occur if
drivers try to speed through an intersection to avoid waiting
in a queue near the railroad crossing.
Time: Medium. Effectiveness: Tried.

G4 – Relocate signal hardware out of clear zone
(HTML | PDF).
WHERE TO USE – Signalized intersections where signal hardware
is located within the clear zone or is a sight obstruction
(particularly on high-speed approaches).
Time: Short. Effectiveness: Tried.

G5 – Restrict or eliminate parking on intersection approaches
(HTML | PDF).
WHERE TO USE – Signalized intersections with permitted parking
on the approaches that may present a safety hazard either by
blocking sight distance or due to parking maneuvers.
Time: Short. Effectiveness: Proven.